Renewable Energy Technology Assessments - Kauai Island Utility ...

Kaua’i Island Utility Cooperative
Renewable Energy Technology Assessments 9.0 Wind
turbines will be an option for Kauai. Use of large turbines may improve performance and
cost slightly.
There are a variety of factors to consider with respect to constructing a wind
project. Simply stated, if the project terrain is too remote or steep, special measures will
have to be taken for construction that may increase the capital cost to non-economical
levels. The most important factors to consider are ability to set up a large crane for
erection of the towers and nacelles and transportation of the towers, nacelles and blades
to the project site. The length of a utility-scale wind turbine blade is routinely over 25
meters (80 ft) and they are always shipped in one piece. Access by a suitable road must
be considered when siting the project.
Projects on Kauai would involve a number of turbines totaling a name plate
capacity around 7 MW as agreed with KIUC. Some options include: 10 Vestas V47s for
a name plate capacity of 6.6 MW, 7 Bonus 1 MW turbines for 7.0 MW, 20 Suzlon 350
turbines for 7.0 MW, 5 GE 1.5 turbines for 7.5 MW (assuming crane availability), or a
number of other options. Final turbine size and manufacturer should be made in
consideration of actual wind data for the site, crane availability, cost, and other factors.
A Vestas V47 660 kW turbine with a hub height of 50 meters has been used in the
analysis herein. A different turbine may be more appropriate, but the V47 will give a
reasonable idea of potential since the uncertainty in the available data is greater than any
differences between turbines. A taller tower will almost always result in greater power
production and should be weighed against constructability, cost, and visual impact.
9.4.3 Project Conceptual Design
This section provides a general description of the layout of a project placed on the
high and moderate priority sites.
A wind plant in the Kalaheo area would likely involve one or two rows of wind
turbines situated to the south west of Kalaheo on private lands or near the coast on
Alexander & Baldwin land in areas of class 5 winds. The row(s) would be oriented
approximately north-south to take advantage of the predominant winds from the east. A
central power collection station and step-up transformer would add power directly to a
major transmission line.
A wind plant in near Anahola, would involve constructing a new road (if one does
not exist) onto the windy ridge of Puu Ehu on state land and placement of turbines along
the ridge for maximum wind collection. From a common power collection point and
transformer, new power lines would bring power to the nearby transmission line.
21 March 2005 9-15 Black & Veatch